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If the SX-8(4) is not detected, when it was running fine yesterday, how do I determine if it is a software or hardware issue?

Run NewTekRTME from a command prompt, twice. The second time when winrtme starts you will get a window full of status info. In that mess you will find a line that either reads Analog daughter card found at... or No analog daughter card found. If it finds the daughter card the power connection is good, the bridge card is seated correctly and the daughter card is probably OK.

Component noise

We see a modulated signal riding on each step of the color bar pattern. There are 6 ripples on each setup. This pattern is in sync with the color bar as it does not move. It looks like this signal is about 816khz.

This type of problem is due to a low level high frequency noise component in the incoming video. The VT card expects a properly filtered video signal to be fed into it. When a video signal with this type of noise is fed in, it causes the video decoder to not work right by causing aliasing when the video signal is sampled. An oscilloscope, rather than a waveform monitor, is needed to see the noise coming from the video source. The incoming video signal should be properly filtered before entering the VT system. Frequencies above 6.5mhz will cause problems by interfering with the 13.5mhz sampling frequency. Generally the noise we've seen on various sources is between 12 and 15 mhz. NewTek is evaluating which available filter on the market would work best to eliminate this incoming noise.

Some users had the same observation with VT[4] - but when they were troubleshooting they borrowed a different digital switcher and still saw the same problems. They traced it back to dirty line power going to the CCUs. Once they cleaned that up the problem went away. They are now are using a SurgeX power conditioner and then a UPS to feed the video equipment a clean line... it also helped to put the refrigerator on a different circuit.

What is the Tally/GPI Pin outs?

Pin

Description

1

LED 1

2

LED 2

3

LED 3

4

LED 4

5

LED 5

6

LED 6

7

LED 7

8

LED 8

9

GND

10

GND

11

No Connect

12

GPI 0

13

GPI 1

14

3.3 volt power

15

No Connect

The led outputs are current sinking (goes low when active) and you should use at least a 200 ohm current limiting resistor in series with an external led. There is also a 200 ohm resistor in series with this signal inside bob. These LED signals are just copies of the tally LEDs on bob. The curcuits go logic low when activated. The GPI pins are connected thru 200 ohms series resistance to the Microchip PIC16F872 micro controller I/O pins. The data sheet for this micro controller lists 25 mA maximum current source/sink on any I/O pin.

The GPI can pins support a normally open switch between the gpi pin and ground.